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Homework Help: Orbital Question

  1. Oct 30, 2006 #1
    Find the orbit radius of an earth satellite in a circular orbit if the period if 1d.

    I'm at a dead end. So far I have;

    r^3 = (GMT^2) / (4(pi)^2)

    r^3 = (6.67*10^(-11) * 6*10^(24)) / (4 * pi^2)

    and I get

    r = 21642

    The book says 42.2Mm. I'm only off by a couple of million meters, hahaha.

    Where am I going wrong?

  2. jcsd
  3. Oct 30, 2006 #2
    You need to use the value of T in seconds for the constants you used to be correct.
  4. Oct 30, 2006 #3
    Argh!!!! Thud, thud, thud ....

    That's the sound of me banging my head against the wall!

    Thanks for the quick reply.

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